There are a wide variety of mapping and positioning technologies. By way of example, many modern smartphones and mobile devices use the Global Positioning System (GPS). In a typical implementation, the smartphone receives signals from multiple GPS satellites. The GPS signals help indicate the distance between the smartphone and the satellites. The smartphone then uses the GPS data to determine its location, which is typically represented as a geocoordinate or GPS coordinate (e.g., a pair of latitude and longitude coordinates.) The GPS system is used in a wide variety of mapping applications and can be used to pinpoint the location of almost any outdoor landmark, region or building.
One disadvantage of the GPS system, however, is that it is ineffective or substantially less effective in indoor environments, because the walls and ceilings of a building may block the satellite signals. Thus, there are ongoing efforts to develop systems that can identify the location of indoor rooms, structures and other areas where a GPS signal cannot be received.